Hello Sathishkumar Sankar

The common points in all the three processes is workpiece acts as a conductive element (Sometimes non conductive in ECDM) ECM has some drawbacks when compared to EDM like corrosivity, but tool wear is less in ECM and ECDM. good surface finish is obtained in ECM.

When talk about initial cost ECDM is highly costly but produces higher MRR when compared to other two processes.

Based on your requirements and Pro's and Con's, you can choose the process.

Good luck

PVR

Dear S . Sathishkumar,

First of all I agree with P Venkateshwar Reddy on every aspect.

Additional to these, I would like to emphasize few points from workpiece geometry, application and requirements perspective:

- You need to use part geometry specific cathodes (tools) for sink EDM and ECM, but for Wire EDM or for ECDM you can use generic tools such as a wire or a cylindrical rod.

- Wire EDM can be used generically for both rough and finishing operations and it is also the same for sink EDM. If you play around with parameters of these processes, you can achieve a good surface quality with a bit of increase in processing times.

- The surface quality of ECDM may not be as good as other processes with the current technology common to different machine manufacturers. But you can use this process for efficient roughing with high material removal rates.

- ECM can mostly be used for semi roughing and finishing operations since it will need a passage way around workpiece for electrolyte flow. If you just mentioned ECM but not PECM also with old technology, you should need a large brewery for conditioning the electrolyte.

I hope these informations will be useful for you.

Regards,

Read this article

Article Comparative studies of ecm, edm and ecam

Four short comments on Özgür's comment. 1. For EDM and ECM I do not necessarily need specific cathodes, that is ED-Milling or EC-Milling. 2. It is not so easy, as I said, that you only have to play something with the process parameters between roughing and finishing. It is crucial whether they really want to optimize (as compared to other machining methods) or just look for the optimal parameters of their machine. A real optimization also takes into account the treatment of the process control (technology, process energy source, connection conditions), the process regulation and the safety control. 3. ECDM means ECM as an assisting process and EDM as the main ablation process, but I think they also mean the reverse process combination. That for the surface quality is poor, can not be claimed in principle. With the hybrid methods, they can also get shiny surfaces without any problems. The actual problems arise for the machining accuracy and the process analysis. 4. How do you know that ECM can only be used for semi-roughing and finishing operations? Problem with the ECM (high removal rate) is the generation of the working gap, because very high removal rates (contamination) are achieved. The consequence is then a larger working gap and consequently a lower machining accuracy. If you want to improve the machining accuracy, then it is basically at the expense of processing time. The PECM is mainly used for fine machining and special surface qualities, or for micro machining.

Best regards Hans Peter

chemical machining is "affordable " for "exotic" material or extremely complex shapes in relative high volume and it is subject to harder environmental regulations. ECM also requires good ventilation due to hydrogen which is releasing as part of the process.

I would go with EDM type.

Thank you for your valuable suggestions honorable professors.....

i am waiting more suggestion from experts ....

Each one of above processes field of applications and I think that ECDM process combined between EDM and ECM and used to enhance the surface finish and metal removal rate which obtained by EDM process.